Method of separating emulsions.



m. mm,

F. W. ARVINE. METHOD OF SEPABATING EFflULSIUPdS.

(Application filed Feb. 7, 1898.) (No Model.)

W/ T/VESS W. JM

MVEN 70/? Patented July as, I899.

Usrrrnn 'S'ra'rns PATENT @rtrcn FREELING w. -ARV-INE, o NEw YORK, N. Y.

METHOD OF SEPARATHNG EMULSlONS.

SPECIFICATION forming part of Letters Patent No. 629,059, dated July 18, 1899. v Application filed February 7, I398- Serial No. 669,392. (No specimens.)

T0 ail whom it may concern.-

Be it known that I, FREELING W. ARVINE, a citizen of the United States, residing at New York, county of New York, and State of New York, have invented a new and useful Improvement in Methods of SeparatingEmulsions and Mixtures of Water, Oil, and Sedimentary or Floating Matters, which improvement is fully set forth in the following specification. I

This invention relates to a method for the treatment of water-gas tar. The oil or tar obtained in the manufacture of water-gas is often largely composed of anemulsion which often has the appearance of a thick mixture of water, oil, and lampblack, with more or less free oil floating upon it, and sometimes a little water slowly collecting at the bottom. The mixture already mentioned, seems never to separate by subsidence under any circumstances. Many expensive and unsuccessful attempts have been made to remove the oil in a practical manner. I have discovered that in the case of water-gas tar the solid portion of this mixture or emulsion, which looks like lampblack, is really fusible pitch in a state of very fine comminution; also, that if this pitch-dust be separated then the other portions-the oil and water-soon separate on standing. In like manner other persistent emulsions of petroleum residues and coal-tar oils containing solidmatters all separate from the water with which they are associated upon the removal of the solid element, which seems necessary to the emulsion. Sometimes this emulsion is like liver in appearance and con sistency and contains but a'very small por tion of solid matter. Such mixtures as these are generally thrown away from gasworks and oil-works in the easiest manner possible.

- The term water-gas is intended to distin guish this tar,? which is a by-product in the manufacture of water-gas, fromthe tar.

obtained ordinarily in the manufacture of coal-gas'and called" coal-tar. The watergas tar is not a combination of materials or substances in layers, but part of it is a mixture in persistent and practically permanent I emulsion. This emulsion is heavier than the clear fluid tar, which floats upon and above the emulsion, which it is the object of my invention to economize by separating theto separate,

mud, which I can melt into pitch, and the oil port-ion, which, being freed from water and sediment, (finely comminuted pitch,) is usefulfor fuel and other purposes.

In carrying out my method I proceed in the following manner: After drawing off such oil from the top and water from the bottom as may be separated by warmth and standing ashort time, the mixture is forced through felt, canvas, or any suitable filtering medium by means of a filter-press or centrifugal machine or like device of any usual construction. In' this operation the solid matter is collected in a cake on the filters and the oil and water are run into receptacles, where the water soon settles, and being drawn off leaves clean oil. When, however, the'oil is as heavy as the Water or when the emulsion is very thick or livery, this plan alone is not sufiicient. In such case I add some soluble substance capable of increasing the gravity of the water and having such affinity for water as to destroy the emulsion beforeat tempting to'filtr out the solid matter. Sodium sulfate, residue from acid-works, is desirable when the emulsion is alkaline; but the same compound in a neutral state is generally desirable. It is added to increase the weight of the water and destroy its affinity for the other constituents of the emulsion. Almost any cheap and available acidand alkali compound soluble in water may answer well and only needs to be stirred up with the mixture, preferably with heating, until the water begins which can be seen in a test-glass. When the mixture has-a curdled or flocky appearance, it maybe filtered in any convenient manner. The ordinary filter-press is useful for this purpose, and is so arranged as to finish the pressing and wash the cake by introducing steam, hot water, and petroleum naphtha or any desired solvent or solvents to remove the last traces of oils and chemicals fromt e press cakefi which is simply melted to form pitch. Whenever the pitch istoo fusible, water may be preferable to steam to clear the cake of the greater portion of oil. I use petroleum naphtha or other petroleum products finally to clean and sweeten the cake from water-gas tar, which is generally scarcely soluble in most petroleum products.

The drawing accompanying this application, with the parts shown in diagram, will further explain my process, the relative sizes and arrangement of parts of the apparatus being for purposes of illustration only.

In the said drawings, A is a tank of any desired capacity. S is a coil of steam-pipe for the purpose of warming the material in the said tank.

F is a filter-press. same.

D is a tank arranged to receive the discharge from the pan.

P is a forcepump.

The operation is as follows: The refuse material is received into the tank A, where it is warmed by means of the coil of steam pipe S, and the salts are stirred in. WVhen heated and mixed suffici ently, the mass is forced by the pump P into the filter-press F through a suitable pipe B, and upon the cloths of the press the solid matter deposits and forms a hard cake. The oil and water drain into the pan 0 and flow into the tank D, where they separate rapidly and may be drawn off in turn by faucets conveniently placed.

Many other forms of forcing devices and filtering apparatus may answer well to carry out my process. I The filter-press-ontlined in the drawing is a kind common in trade and with an ordinary steam force-pump is found to be a convenient form. The filter-cloths are folded over distance-plates and a screw with a hand-wheel closes them securely.

C isa pan beneath the sion about three hundred pounds, more on less, of dry salt.

No claim is made herein to the apparatus herein shown and described, as the same may form the subject-matter. of a separate appli cation.

What I claim as new is- 1. The herein-described method of treating water-gas tar, which consists'in adding a coagulent, filtering under pressure, and then heating, substantially as described.

2. The herein-described method of treating Water-gas tar, which consists in adding a soluble substance to increase the gravity of the water, then filtering under pressure and then washing, substantially as specified.

3. The herein-described method of treating "water-gas tar, which consists in salting and heating the same, filtering, then pressing, washing and fusing the residue or cake, substantially as described.

FREELING \V. ARVINE. \Vitnesses:

CHAS. WAHLERS, CHARLES G. COE. 

